U.S. patent number 4,316,169 [Application Number 06/207,998] was granted by the patent office on 1982-02-16 for windings for electrical inductive apparatus.
This patent grant is currently assigned to Tokyo Shibaura Denki Kabushiki Kaisha. Invention is credited to Takeshi Higuchi, Tsuneharu Teranishi.
United States Patent |
4,316,169 |
Teranishi , et al. |
February 16, 1982 |
Windings for electrical inductive apparatus
Abstract
Windings for electrical inductive apparatus are disclosed which
include a plurality of first and second pairs of disc coil sections
arranged in a stack. Each of the second pairs of disc coil sections
are disposed between the first pairs of disc coil sections. Each of
the disc coil sections includes two conductors wound in parallel
with each other. Each of the two conductors at the inner ends of
each section in the first pair of disc coil sections are connected
to each of the two conductors at the inner ends of each section in
the second pair of disc coil sections, respectively. One conductor
at the outer ends of the two sections in the second pair of disc
coil sections is connected to one conductor at the outer ends of
the two sections in the first pair of disc coil sections. Each of
the three conductors at the outer end of two sections in the second
pair of disc coil sections is connected to one of three conductors
at the outer end of two sections in the next first pair of disc
coil sections, respectively.
Inventors: |
Teranishi; Tsuneharu (Yokohama,
JP), Higuchi; Takeshi (Yokohama, JP) |
Assignee: |
Tokyo Shibaura Denki Kabushiki
Kaisha (Kawasaki, JP)
|
Family
ID: |
15461834 |
Appl.
No.: |
06/207,998 |
Filed: |
November 18, 1980 |
Foreign Application Priority Data
|
|
|
|
|
Nov 19, 1979 [JP] |
|
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54-148837 |
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Current U.S.
Class: |
336/70;
336/187 |
Current CPC
Class: |
H01F
27/343 (20130101); H01F 27/2871 (20130101) |
Current International
Class: |
H01F
27/34 (20060101); H01F 27/28 (20060101); H01F
015/14 () |
Field of
Search: |
;336/69,70,186,187 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Kozma; Thomas J.
Attorney, Agent or Firm: Oblon, Fisher, Spivak, McClelland
& Maier
Claims
What is claimed as new and desired to be secured by Letters Patent
of the United States is:
1. A winding for electrical inductive apparatus, comprising:
a plurality of first pairs of disc coil sections, each of said
plurality of first pairs of sections including a first section and
a second section arranged in a stack;
a plurality of second pairs of disc coil sections, each of said
plurality of second pairs of sections including a third section and
a fourth section arranged in said stack;
wherein each of said second pairs of disc coil sections are
disposed between said first pairs of disc coil sections;
wherein each of said first, second, third and fourth sections
include two conductors wound in parallel with each other;
wherein each of two conductors at an inner end of said first
section are connected to each of two conductors at an inner end of
said third section, respectively;
wherein each of two conductors at an inner end of said second
section are connected to each of two conductors at an inner end of
said fourth section, respectively;
wherein a first conductor at an outer end of said third section is
connected to a first conductor at an outer end of said second
section;
wherein a second conductor at the outer end of said third section
is connected to a first conductor at an outer end of a first
section in a first pair of disc coil sections disposed adjacent to
said second pair of disc coil sections;
wherein a first conductor at an outer end of said fourth section is
connected to a second conductor at the outer end of said adjacently
disposed first section; and
wherein a second conductor at the outer end of said fourth section
is connected to a first conductor at an outer end of a second
section in said adjacently disposed first pair of disc coil
sections.
2. The winding as recited in claim 1, wherein: said first and
second pairs of disc coil sections are disposed adjacent to each
other such that said first section is disposed adjacent to said
second section, said third section is disposed adjacent to said
second section, and said forth section is disposed adjacent to said
third section.
3. The winding as recited in claim 2, wherein: each of said two
conductors at the inner end of said first section are connected to
each of said two conductors at the inner end of said third section
by being transitted via an inner transition, respectively;
each of said two conductors at the inner end of said second section
are connected to each of said two conductors at the inner end of
said fourth section by being transitted via an inner transition,
respectively;
said second conductor at the outer end of said third section is
connected to said first conductor at the outer end of the first
section in the first pair of disc coil sections disposed adjacent
to said second pair of disc coil sections by being transitted via
an outer transition;
said first conductor at the outer end of said fourth section is
connected to said second conductor at the outer end of said
adjacently disposed first section by being transitted via an outer
transition; and
said second conductor at the outer end of said fourth section is
connected to said first conductor at the outer end of said second
section in said adjacently disposed first pair of disc coil
sections by being transitted via an outer transition.
4. The winding as recited in claim 3, wherein:
each of said two conductors at the inner end of said first section
are connected to each of said two conductors at the inner end of
said third section without being transposed, respectively; and
each of said two conductors at the inner end of said second section
are connected to each of said two conductors at the inner end of
said fourth section without being transposed, respectively.
5. The winding as recited in claim 3, wherein:
each of said two conductors at the inner end of said first section
are connected to each of said two conductors at the inner end of
said third section by being transposed, respectively; and
each of said two conductors at the inner end of said second section
are connected to each of said two conductors at the inner end of
said fourth section by being transposed, respectively.
6. The winding as recited in claim 4, wherein:
an inner conductor at the outer end of said third section is
connected to an outer conductor at the outer end of said second
section;
an outer conductor at the outer end of said third section is
connected to an inner conductor at the outer end of the first
section in the first pair of disc coil sections disposed adjacent
to said second pair of disc coil sections;
an inner conductor at the outer end of said fourth section is
connected to an outer conductor at the outer end of said adjacently
disposed fist section; and
an outer conductor at the outer end of said fourth section is
connected to an inner conductor at the outer end of the second
section in said adjacently disposed first pair of disc coil
sections.
7. The winding as recited in claim 5, wherein:
an inner conductor at the outer end of said third section is
connected an inner conductor at the outer end of said second
section;
an outer conductor at the outer end of said third section is
connected to an outer conductor at the outer end of the first
section in the first pair of disc coil sections disposed adjacent
to said second pair of disc coil sections;
an inner conductor at the outer end of said fourth section is
connected to an inner conductor at the outer end of said adjacently
disposed first section; and
an outer conductor at the outer end of said fourth section is
connected to an outer conductor at the outer end of the second
section in said adjacently disposed first pair of disc coil
sections.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates in general to electrical inductive
apparatus, and more particularly to windings for such
apparatus.
2. Description of the Prior Art
Electrical inductive apparatus, such as transformers and reactors,
commonly utilize a high voltage winding which includes a plurality
of electrically connected disc coils arranged in an axially aligned
stack about a winding leg of a magnetic core. When an impulse
voltage, such as caused by lightning or switching, is applied to
the electrical inductive apparatus, a potential distribution along
an axis of the winding thereof is determined by the distribution
constant .alpha.. The distribution constant .alpha. is equal to the
square root of the ratio of the capacitance Cg of the winding to
ground to the series capacitance Cs of the winding.
The smaller the distribution constant .alpha., the more linear the
potential distribution, due to the impulse voltage, will be across
the axial direction of the winding, and the smaller the magnitude
of the transient potential oscillation within the winding will be.
Since the distribution constant .alpha. can be reduced by
increasing the series capacitance Cs of the winding, various kinds
of high voltage windings having increased series capacitance have
been utilized. Interleaved windings are well known examles of such
windings.
FIG. 1 shows one example of an interleaved winding. In FIG. 1 a
conductor 1 through 10 and a conductor 11 through 20 are wound in
parallel with each other on an insulating tube 102 via a ductrail
103 to form a pair of disc coils. The conductor 10 is connected to
the conductor 11 at a point X so that the conductor 1 through 10
and the conductor 11 through 20 are connected in series with each
other. The conductor 20 is also connected to a conductor 21 of a
next pair of disc coils. Thus an interleaved winding 101 is made by
connecting a plurality of the pairs of disc coils in series with
each other, as is apparent to those skilled in the art. In the
interleaved winding 101, the conductor 1 through 10 and the
conductor 11 through 20 are wound in parallel with each other, thus
being interleaved, and form a capacitor therebetween, the series
capacitance of which becomes large. However in the interleaved
winding 101, it is essential that two conductors be connected at
one point X per pair of disc coils as shown in FIG. 1. It is also
essential to wind the two conductors in parallel with each other in
order to form a pair of disc coils.
In electrical inductive apparatus for large current use, an
interleaved winding where a plurality of conductors are wound in
parallel with each other in each of the disc coils is used. FIG. 2
shows an example of such an interleaved winding with a plurality of
pairs of disc coils having three parallel conductors al through
a72, b1 through b72, and c1 through c72. In making a pair of disc
coils in the interleaved winding 101A shown in FIG. 2, two times
three conductors namely six conductors, must be wound in parallel
with each other. Also it is essential to connect three conductors
at point X respectively per pair of disc coils (a6 to a7, b6 to b7,
c6 to c7).
As described above, it is difficult and time consuming to make a
conventional winding where many conductors are wound in parallel
with each other in each of the disc coils.
SUMMARY OF THE INVENTION
Accordingly, one object of this invention is to provide a novel
winding for an electrical inductive apparatus which can be made
easily and rapidly.
Another object of this invention is to provide a novel winding for
an electrical inductive apparatus having a large series
capacitance.
Still another object of this invention is to provide a novel
winding for an electrical inductive apparatus having improved
characteristics with respect to impulse voltages.
These and other objects of this invention can be achieved by
providing windings for electrical inductive apparatus which include
a plurality of first pairs of disc coil sections, each including a
first section and a second section arranged in a stack, and a
plurality of second pairs of disc coil sections, each including a
third section and fourth section arranged in the stack. Each of the
second pairs of disc coil sections are disposed between the first
pairs of disc coil sections. Each of the first, second, third and
fourth sections include two conductors wound in parallel with each
other. Each of the two conductors at the inner end of the first
section are connected to each of the two conductors at the inner
end of the third section, respectively. Each of the two conductors
at the inner end of the second section are connected to each of the
two conductors at the inner end of the fourth section,
respectively. One conductor at the outer end of the third section
is connected to one conductor at the outer end of the second
section. The other conductor at the outer end of the third section
is connected to one conductor at the outer end of a first section
in a first pair of disc coil sections disposed adjacent to the
second pair of disc coil sections. One conductor at the outer end
of the fourth section is connected to the other conductor at the
outer end of the adjacently disposed first section, and the other
conductor at the outer end of the fourth section is connected to
one conductor at the outer end of a second section in the
adjacently disposed first pair of disc coil sections.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete appreciation of the invention and many of the
attendant advantages thereof will be readily obtained as the same
becomes better understood by reference to the following detailed
description when considered in connection with the accompanying
drawings, wherin:
FIG. 1 is a partial sectional elevation view of a conventional
interleaved winding;
FIG. 2 is a partial sectional elevation view of a conventional
interleaved winding having three parallel conductors;
FIG. 3 and FIG. 4 are partial sectional elevation views of a
winding according to two preferred embodiments of the present
invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings, wherein like reference numerals
designate identical or corresponding parts throughout the several
views, and more particularly to FIG. 3 thereof, a winding 101B
according to a preferred embodiment of this invention is shown.
In the following discussion, the term "transition" refers to the
continuation of a single conductor from one disc coil section to
another without the use of splices or other physical coupling
means. The conductor retains both its physical and electrical
integrity during the "transition". This is to be distinguished from
the term "connection" which is a broad concept encompassing both
the term "transition" and a narrower concept wherein a junction or
splice connection exists between two or more conductors.
In FIG. 3, two conductors, a and b, are wound in parallel with each
other from the inside to the outside of the winding 101B in an
initial section 1A. An inner conductor (a9) located at the outer
end of the section 1A is transitted to an outer conductor (a10)
located at the outer end of a section 1B positioned adjacent to the
section 1A via an outer transition 11a, and the outer conductor
(b9) located at the outer end of the section 1A is transitted to an
inner conductor (b10) located at the outer end of a section 1C
positioned adjacent to the section 1B via an outer transition 12a.
At the outer end of the section 1B, a new conductor c is added
inside the conductor (a10) transitted from the section 1A, and at
the outer end of the section 1C a new conductor (c19) is added
outside the conductor (b10) transitted from the section 1A. The two
sections 1B, 1C are made by winding the two conductors, ac and bc
respectively, in parallel with each other from outside to inside.
At each of the inner ends of the sections 1B, 1C, two conductors
thereof are transitted to two conductors at each of the inner ends
of the following sections 1D,2A via inner transitions 13a, 14a
without being transposed, respectively. The two sections 1D, 2A are
made by winding the two conductors, ac and bc respectively, in
parallel with each other from inside to outside. An inner conductor
(c18) at the outer end of the section 1D is connected to the outer
conductor (c19) at the outer end of the section 1C, which is added
at the beginning of the winding of the section 1C, at a point X.
The outer conductor (a27) at the outer end of the section 1D is
transitted to an inner conductor (a28) at the outer end of a
section 2B located adjacent to the section 2A via an outer
transition 15a. An inner conductor (b27) at the outer end of the
section 2A is transitted to the outer conductor (b28) at the outer
end of the section 2B via an outer transition 16a, and the outer
conductor (c36) at the outer end of the section 2A is transitted to
an inner conductor (c37) at the outer end of a section 2C located
adjacent to the section 2B via an outer transition 17a. The
transitions 16a and 17a from the section 2A to the sections 2B and
2C respectively, are similar to the transitions from the section 1A
to the sections 1B, 1C via outer transitions 11a, 12 a. At the
outer end of the section 2C a new conductor (a46) is added outside
the conductor (c37) transitted from the section 2A. The two
sections 2B, 2C are made by winding the two conductors, ab and ac
respectively, in parallel with each other from outside to inside.
The remainder of the winding 101B is made by continuing to wind the
conductors as described above.
Being constructed as described above, the winding 101B with three
conductors wound in parallel with each other as a whole is
obtained. The order of the turns of the three conductors in the
winding 101B are a1 through a72, b1 through b72 and c1 through c72
as shown in FIG. 3. In making a disc coil in the winding shown in
FIG. 3, only two conductors are wound parallel with ech other. To
make the winding 101B only three connections at the points X are
needed for twelve disc coils.
The winding 101B shown in FIG. 3 has the same number of turns and
the same number of parallel conductors as a whole as those in the
interleaved winding 101A shown in FIG. 2. Therefore, comparing the
winding 101B with the interleaved winding 101A, the number of
points connecting conductors in the winding 101B is only one-sixth
of the necessary connecting points in the interleaved winding 101A,
and the number of conductors wound in parallel with each other is
reduced by one-third. Accordingly, the winding 101B can be made
easily and rapidly.
Next, a series capacitance of the winding 101B, according to a
preferred embodiment of this invention, will be determined by
calculating the static electric energy stored among the conductors
in the winding. The static electric energy E per section of a
winding is generally determined by equation (1):
WHERE:
C: equivalent capacitance per section
V: voltage per section (V=ne)
Ct: capacitance between conductors per turn
Vt: voltage between conductors
n: the number of turns per section
e: voltage per turn
In winding 101B, each of the three conductors a, b and c is wound
in eight sections out of the twelve sections 1A through 3D,
respectively. Therefore the average number of turns per section n
is:
where m is the actual number of turns of the conductor a, b or c
per section respectively. In the case of the winding 101B, m=9 and
n=6.
Next the voltage Vt between the conductors in each section will be
determined. In sections 1B, 1C, 2C and 3B, the number of the
position where Vt=me is m, and the number of the position where
Vt=(m+1)e is (m-1). In sections 1D, 2A, 3A and 3D, the number of
the position where Vt=me is m, and the number of the position where
Vt=(m-1)e is (m-1). In sections 1A, 2B, 2D, and 3C, the number of
the position where Vt=e is (m-1). Therefore the total static
electric energy Et for the twelve sections 1A through 3D is:
Therefore, the static electric energy E per section is determined
as:
(3)
Therefore, the equivalent capacitance C per section is determined
by equation (1) and equation (3) as:
On the other hand, a series capacitance of the interleaved winding
101A with three parallel conductors shown in FIG. 2 will now be
determined. In each section the number of the position where Vt=ne
is (5/2)n, and the number of the position where Vt=(n-1)e is
[(n/2)-1]. In the case of the widning 101A, n is also 6. Therefore,
the static electric energy E per section is determined as:
Therefore, the equivalent capacitance C per section is determined
by equation (1) and equation (5) as:
By comparing equation (4) with equation (6), the series capacitance
of the winding 101B, according to the preferred embodiment of this
invention, is one and one half times that of the conventional
interleaved winding 101A having the same number of turns and the
same number of parallel conductors as winding 101B.
In the winding 101B shown in FIG. 3, transpositions are made in the
transitions between the outer ends of two sections but not between
the inner ends; however this invention is not restricted to this
embodiment. In FIG. 4, a winding 101C according to another
preferred embodiment of this invention is shown. This winding 101C
has the same construction as that of the winding 101B shown in FIG.
3 except that transpositions are made in the transitions between
the inner ends of two sections and not between the outer ends. The
winding 101C also has the same effect as the winding 101B shown in
FIG. 3; that is, the winding 101C can be made easily and rapidly.
The winding 101C also has a large series capacitance and has
improved characteristics with respect to impulse voltages.
In the embodiments of the subject invention shown in FIGS. 3 and 4,
the sections 1A through 3D have been illustrated as having a
particular order. However, since other arrangements are possible in
light of the above teachings, the present invention should not be
considered as being limited to the order illustrated. For example,
the ordering of the individual sections can be reversed in pairs.
Thus 1B and 1C can be reversed and 1D and 2A can be reversed.
Similary, other pairs of sections can be reversed.
Obviously, numerous modifications and variations of the present
invention are possible in light of the above teachings. It is
therefore to be understood that within the scope of the appended
claims, the invention may be practiced otherwise than as
specifically described herein.
* * * * *